The invention relates to an aircraft undercarriage mechanism. The invention is to be applied primarily to an aircraft wing landing gear door which must remain safely closed when the landing gear wheels are retained in a wheel bay during flight.
Typically, an undercarriage door is held closed by a locking mechanism comprising a catch and a member engageable with the catch, one of which member and catch is arranged on the undercarriage door and the other of which is arranged on part of the wing. Aircraft wings deflect during flight as various forces acting on the wings vary in magnitude. Such deflection can cause relative movement to occur between the door and the wing which, in turn, transmits force to the locking mechanism which can be a problem and an object of the invention is to provide a door locking mechanism which minimises that problem.